Many operating systems (OSs) include a notification system to notify a user that a new message has been received or a system alert (e.g., low battery alert) has been issued. These messages usually are displayed in a pop-up bubble like window (usually near the system tray) to inform the user. Such an implementation may disrupt the user and force the user to go elsewhere (e.g., switching to another window or process) to respond.
Typically, when a message (e.g., email or IM message) is received, in order to respond to the message, an application associated with that message (e.g., email or IM application) has to be invoked. A separate window and/or a separate process have to be launched or utilized. As a result, the user has to switch from what (e.g., word processor) he/she is doing to another window and/or process to respond or view the entire message. Such a task switch is relatively expensive in terms of processing resources of a computer system.